Creating pthread in qt creator

Hi all,
I am a newbie, I just want to send some messages from pthreads thread function to qt GUI. I am creating thread like this
pthread_create(&thread_read, NULL,&read_data,NULL);.
But I am getting following error
" read_data is not declared in this scope".
I have added
QMAKE_CXXFLAGS+= -std=gnu++0x -pthread -lpthread
LIBS += -L/usr/include -pthread

I have created pthread in main(). I am creating like this
pthread_create(&thread_read, NULL,&read_data,NULL); and I am defining read_data in the same main.cpp like this void * read_data().
Could you please help me with this.